Variable pitch propeller



March 30, 1943. E. LINEHAN 2,315,213 I VARIABLE P ITCH PROPELLER March30, 1943. E. I INEHAN 2,315,213

VARIABLE PITCH PROPELLER y Filed April 15, 1939 2 Sheets-Sheet 2 42 r324 :f Z7 f 26 45 35 40 33 7 32 A5*/ 34 3/ 2/29 Si 22 27 Il', 'Il /l/ l1'/ /ll /0 E5 26 \40 20 a7 4/ l /7 9 Ardiff/ara bhe/7a d Hof. WMA

Patented Mar. 30, 1943 UNITED STATES PATENT OFFICE VARIABLE rrronPnorELLER Edward mnehan, Hillman, Mimi. Application April 15, 1939,serial N0. 267,999

2 claims. (cl. 17o-lss) My invention relates to an improvement invariable pitch propeller wherein it is desired to provide a propeller inwhich the pitch is automatically variable and which is capable ofpermitting movement of the blade into a fullfeathering position in casethe motor should cease to function.

Automatic pitch propellers have been constructed in the past. Many ofthese propellers are capable of accomplishing much the same result tothat desired in the present invention,

but my construction is designed to require an` exceedingly small numberof parts to function in the proper manner.

It has been found that unless thev propeller mechanism is properlyconstructed, the blades of the propeller will not move intofull-feathering position in case one of the motors should cease tofunction. In any other position of the blades. the angularity of theblades cause the blades to rotate the crank shaft of the motor, causingthe motor to draw fuel from the fuel tanks which ordinarily is notexploded. An accumulation of unburned fuel will then be forced into thehot exhaust pipe, creating danger of an explosion and endangering thelives'of the personsin the plane. Furthermore, when the motor ceases tofunction for any reason, it is desirable that the rotation of the motorbe stopped as soon as pos.

sible, in order to prevent further damage of the motor by any partsofthe same .which might be broken.

It is an object of my invention to provide a device which willautomatically permit the blades to move into full-feathering position inan extremely short space of time, and which if desired may be operatedmanually to cause such full-feathering of the blades to take place.

It is a purpose of my invention to operate the propeller mechanism tocontrol the angularity of the blades by means of a rotating disc drum orelement and to create friction or in any suitable way to change thespeed of rotation of this disc with respect to that of the propellershaft.

variable pitch propeller mechanism in which the propeller blades arenormally urged into` one exposition. In the rotation of the propellershaft,

if the speed o'f rotation of the shaft increases, additional friction iscreated to rotate the blades to greater angularity, while if the speedof rotation of the propeller shaft decreases, the friction tendency willbe lessened, permitting the propeller blades to rotate in a manner todecrease the pitch of the same. Thus, the propeller blades are adjustedin angularty in accordance with variations in the thrust of thepropeller blades in operation and may also be manually controlled. v

It' is a purpose of the preferred form of my invention to provide aspring or resilient means for resiliently urging the blades of thepropeller toward low pitch and to provide means for moving thepropellers toward a higher pitch. Whell this means for moving theypropeller toward a higher pitch is removed, the propeller willautomatically move back into low pitch without any means except thespring means described and the normal tendency of the blades to move inthis direction when other pressure is released,

causing such movement.

These and other objects and novel features of my invention will be moreclearly and fully sct forth in the following specification and claims.In the drawings forming a part of my specication: Figure 1 is across-sectional View through my variable pitch propeller mechanism, thesection being taken on a plane through the axis of the propeller shaft.

Figure 2 is a cross-sectional vieW through my variable pitch propellermechanism, the position of the section being indicated by the lines 2-2of Figure 1.

Figure 3 is asection taken on a plane .parallel to Figure 2, theposition of the section being indicated by the line 3-3 of Figure 1. l

Figure 4 is another section taken on planes parallel to the sections inFigures 2 and 3, the

position of the section being indicated by the line 4-4 of Figure 1.

The variable pitch lpropeller mechanism A isv shown of a particularshape and conformation. but may of course be widely changed in shape andproportion to lfit varying requirements. The variable pitch propellermechanism A is designed to be mounted upon the propeller shaft I9 whichis shown having a substantially cylindrical portion I I, a splineportion I2, a threaded portion i3, and an attaching portion I4,preferably cylindrical in section. The splined portion I2 of the shaftI9 extends through a spider I5 to which the propeller blades are securedin a manner which will be laterdescribed, and lto which the outer casingI9 of the mechanism A is secured through spacing blocks I1.

The spider I5 is best illustrated in Figure 3.

of the drawings and is shown provided with ears or lugs I9 to .which thespacer blocks I1 are attached by means of bolts or other suitable means.The spacer blocks I1 are provided with slots or apertures into which thelugs or ears I9 extend, and the bolts 20 extend through portions of thespacer block I1 on either side of these apertures for accommodation ofthese lugs I9 as well as through the lugs.

Between the attachment with the spacer block I1, the spider is providedwith flattened surfaces 2I from which the sleeves 22 extend. The sleeves22 are preferably each formed with a pair of bearing surfaces 23 and 24which engage cooperating bearing surfaces on a tapered bushing 25recessed in the end or shank A26 of the propeller blades 21.

A ring 29 is secured to the end of the shank 29 oil each propeller, andthis ring 29 is provided along a segmental portion of its periphery withgear teeth 30 as indicated in Figure 1 oi' the drawings. A pair ofsupporting rings 3| having a relativelyilexible washer 32 therebetweenare interposed about the shank 26 of the propeller between the ring 29and the anti-friction bearing 33. The anti-friction bearing 33 ispreferably of the split type so that it may be replaced, and is held invplace by a threaded ring 34 which may also be formed of two halves ifdesired so that it may be removed from the propeller shank withoutremoving the ring 29. When the rings 34 have been threadably secured tothe casing I9, the natural tendency for the blades 21 to be pulledoutwardly by centrifugal force is overcome by engagement with theanti-friction bearing 33 and even while considerable centrifugal forceis urging the blades outwardly, they may be turned easily because of thebearings 33.

Within each of the sleeves 22 and extending in to the body of thepropeller blades 21, I provide a pair of relatively rotatable shafts 35and 39. The shaft 35 is provided with an oiT-set pin or key 31 whichprevents rotation of the shaft 35 with respect to the spider I5, and oneend of the spring 39 is vanchored at 49 thereto. A projecting end 4I onthe shaft 35 extends into an axial aperture in the shaft 39 so that theshafts 35 and 39 may be supported in alignment, but relativelyrotatable. The outer end of each spring 39 is secured at 42 to the shaft39. The shaft 39-is secured by an off-set pin 43 or any other suitablemeans to the propeller blade 21.

It will be noted that the shafts 35 and 39 are so constructed as to notinterfere with axial movement of any of the blades 21, but they are sopositioned as to create a tendency for the blade other forces act uponthe blade, the blade will remain in low pitch position. 'I'he gear teeth39 on the ring 29 are designed to engage a bevel gear 44 encircling theprojecting end I4 of thepropelier shaft I3. Attached to this bevel gearby bolts 45 or any suitable means, I provide a spur gear 49. These gears44 and 49 are rotatable with respect to the shaft I9 and while theynormally rotate with this shaft, they'are not keyed or otherwiseattached thereto. Apinion 41 upony a shaft 49 engages the gear'49 and isextremely small with respect thereto so that the shaft 49 will rotate anumber of times for each revolution of the gear 49; l

A partition member and support 50 is illustrated secured by bolts 5I orother suitable means to the casing I9. The shaft 49 extends through thepartition 50, and a gear 5I is mounted on the opposite side of thepartition from the pinion 41. The partition 59 thus forms a support forthe shaft 49. The gear 5I' is constantly in mesh with a pinion 52 bestillustrated in Figure 2 of the drawings, which rotates upon the axis 53and which causes rotation of the gear 54. 'I'he shaft 53 is supported inany suitable manner as by the partition 50.

A second shaft 55 is mounted in any suitable manner as by the partition50 and supports a pinion 59 in mesh with the gear 54 and the gear 51which is rotated with the pinion 59. The gear 51 rotates a pinion 59mounted upon a shaft 90 which extends downwardly through the spider isupporting a ring of felt 10 or other suitable material. The ring 99 issupported as illustrated in Figures 1 and 4 by a pair of links 1I and asecond pair of links 12. The links 1I are pivotally attached at 13 toxed supports 14, while they are pivotally secured at their other end 15to ears 19 upon the ring 99. The links 12 are pivotally connected at 11to xed supports 19 and are pivotally secured at their other -end 30 toears 9| on the ring 99. It will be noted that by this arrangement, thering 99 remains parallel to the disc 91 at all times, and that the links1I e and 12 permit the ring to befmoved toward or away from the disc 91.A To actuate the ring 99 toward or away from the disc 91, I provide apair of links 92 pivoted between ears 33 upon the ring 99 and pivoted at34 to bell crank levers 95. The levers 35 are pivoted at 39 to the ilxedsupports 19 and on the opposite side of their xed pivots 39 are pivotedat 31 to link means 39. The links 39 are secured by pins or othersuitable means to a ring 9i which is formed as a part of the collar 92,but is rotatable with respect thereto. The collar 92 is longitudinallyslidable upon a shaft 93, but is designed to rotate with the shaft 93. Afixed collar 34 is 21 to move toward low pitch position. It no 75secured near an end of the lshaft 93 and a spring 95 is interposedbetween the fixed collar 94 and the slidable collar 92. Governor weights99 are .secured by pairs of links 91 between the xed colcollar 92 towardthe fixed collar 94. This movement will cause longitudinal movement ofthe ring 9| and the attaching means 90 so as to draw the links. 89toward the fixed collar 94. This action will tend to pivot the bellcrank 85, raising the link 82 and moving the ring 69 upwardly toward thedisc 61. If the movement is sufficient, it will cause friction betweenthe felt 10, which is preferably impregnated with oil or other suitablematerial, and the disc 61, tending to slow down the disc 61 with respectto the speed of rotation of the shaft. I0. Any variation in the speed ofrotation between the disc 61 and the shaft I 0 causes rotation of thegear 63, the pinion 62, the gear 6| and the vertical shaft 60. Rotationofthe vertical shaft 60 causes rotation of the pinion 59, gear 51,pinion 56, gear 64, pinion 52, gear 5|, and pinion 49, which causesrotation of the gear 46 and the bevel gear 44. This in turn causesrotation of the ring 29 bearing the teeth 30, thus acting to vary thepitch of the propeller in a manner to increase the same.

The shaft 93 is mounted between a fixed support 99 and an end support|00, and is provided with a bevel gear cooperating with a similarcooperating bevel gear |02 on a shaft |03. The gear |04 is mounted uponthe gear |03 which operates the idle gear |05 which in turn engages thegear |06 on the shaft l0. Rotation of the shaft I0 rotates the gear |06,the gears |05 and |04, shaft |03, and bevel gears |02 and -|0|, torotate the shaft 93. This causes operation of the governor whichcontrols the movement of the ring 69. The shaft |03 and the fixedsupports 99 are secured to the nose plate |01, secured infixed positionin the front of the motor. A housing |09 is designed to surround thecylindrical portion II of the shaft I0 and to contain the governor, `thering 69, and the mechanism for operating this ring; The housing I6 is ofcourse rotatable and rotates in`an aperture |'I0 designed for thispurpose.

In order to provide a manual control for varying the pitch of the blades21, I provide a bell crank I pivoted at I I2 to a fixed support I3. Oneend of this bell crank is pivotally connected to one of the links 89 atthe point II4. A manual control cable ||5 extends through a pivoted lug||6 on the other end of the bell crank lever- III. By pushing on thecontrol cable |I5, the end of the bell crank lever attached to the cableis pivoted upwardly, pivoting the bell crank in a counter-clockwisedirection, causing the bell crank lever 85 to pivot in a clockwisedirection, and pulling the ring 89 away from the disc 61 to withdrawfriction therefrom. By pulling on the control cable I5, the bell cranklever 85 is moved in a counter-clockwise direction, raising the ring 69and creating additional friction against the disc 61. Thus when-it isdesired to increase the pitch manually, the control cable ||5 is pulled,whereas if it is desired to decrease the pitch, the control cable ispushed inwardly. drawing the ring 69 away from the disc 61. The springs39 are then free to pivot the blades 21 toward low pitch position.

A spring |I1 is interposed between a nut ||9 on the cable ||5 and thelug I I6 on the lever |I|. If the control cable ||5 is pushed inwardly,the spring ||1 creates a tendency to pull the ring 69 away from thefriction disc 61. As the governor operates, the bell crank lever III ismoved 1n a clockwise direction by the link 89. This movement compressesthe spring ||1 and accordingly the governor must act against the spring||1 as weil as the spring 95. Accordingly. the governor can operate at ahigher rate of speed without forcing the ring 69 against the frictiondisc 61. Thus as the ship is started from the ground, the control cableI I5 may be pushed inwardly and the propeller shaft I0 will be permittedto act at a higher rotative speed without increasing the pitch of thepropeller blades 21.

Similarly, the spring ||1 may operate to provide the opposite functionand to provide a tendency to push the ring 69 against the disc 61 if thecontrol cable I5 is pulled outwardly. Thus if it is desired to manuallyincrease the pitcl of the blades to an angle more than would normally beassumed by the blades at a particular speed of rotation of the shaft I0,the control cable 5 is pulled outwardly, accomplishing this result. Bypulling the cable ||5 farther out, the head |20 of the cable will'engage against the lug ||6 to cause the-felt on the ring 69 to engagethe friction disc 61 to move the propeller blade into full-featheringposition.

'I'he spider I5 is held in place by a nut I2I on the threaded portion||3 of the shaft I0. A partition |22 parallel to the partition 50 coversthe construction of the device. When the speed of rotation of the shaftI0 increases,the gear |06 on this shaft acts through the gears |05 and|01 1| and 12 in a counter-clockwise direction. This to rotate the shaft|03 which acts through the bevel gears |02 and |0| to rotate thegovernor shaft 93. This increase of speed throws the governor weights 96outwardly, acting through the levers 91 to move the ring 9| of thecollar 92 to the right as viewed in Figure 1. This action acts throughthe pivot pins 90 to move the links 89 to the right, pivoting the bellcrank levers 95 in a counter-clockwise direction and acting through thelinks 82 to move the supporting links action raises the friction pad 10into contact with the disc 61, creating a frictional engagement betweenthe disc 61 and the friction material 10 of the stationary friction disc69.

The disc 61 and the series of gears connected therewith normally rotatewithout relative rotation together with the shaft I0. As the frictionsurface 10 tends to slow down the disc 61 and cause this disc to rotateslower than the shaft I0, relative rotation of the various gears isnecessary. `A small angular movement of the disc 61 causes an extremelysmall angular movement of the gear 44 because of the gear traininterposed therebetweei-. A slowing down of the disc 61 causes theslowing of the gear 64 connected thereto. which in turn rotates thepinion 62 connected thereto. The pinion 62 rotates the gear 6| whichrotates the shaft 60v extending through the spider able with thepropeller blades 21. Thus through the train of gears a slight pressureupon the disc This causes rotation of the gear 63 61 tending to slow thespeed of rotation of thisdisc will act to rotate the blades 21 axially.

The pressure required to change the pitch of the blades to increase thepitch thereof is dependent upon the resistance by the blades to suchrotation. When the friction surface 10 ofthe disc y69 is moved away fromvthe disc 61, the springs 39 within the bladestend to rotate theseblades toward low pitch. Movement of the blades 21 toward low pitch willnormally cause an in.

crease in the speed of rotation of the shaft lil, which in turn will actthrough the governor in the manner described to increase the pitch ofthe blades. Thus the angle of the pitch of the blades is greatlydependent upon the speed of rotation of the shaft i and the resistanceof the blades to any change in pitch.

In the manual operation the cable connector H is provided to pivot thebell crank l l I to move the link 89 by hand in place of throughgovernor control. The manner in which the links 99 are operated by thegovernor weights 96 has been described.. 'I'hese links 89 are alsoattached to the bell crank Hi .which is controlled manually through thecable H5. Y

If it is desired to increase the pitch manually to an angle more thanwould normally be assumed by the blades at the particular speed ofrotation of the shaft I0, the control cable I5 is pulled outwardly, thehead thereof pivoting the bell crank III in a clockwise direction,pivoting the links 99 to the right as illustrated in Figure l,

which in turn pivots the bell cranks 85 in a counter-clockwisedirection, acting through the links 82 to pivot the supporting links 1Iand 12 in a counter-clockwise direction and raising the disc 89 bearingthe friction surface 1li into engagement with the disc 61. Thus bypulling on the control cable IIS, the blades may be axially rotated inthe same manner as if the speed of rotation of the shaft Il) had beenincreased. The amount to which the blades 21 may be pivoted by thecontrol cable I i5 is dependent upon the length of time the frictiondisc 1li is held in contact with the disc 61. -The blades may thus bemerely actuated to increase the pitch thereof, or may be moved intofeathering position.

Because of the series of gears interposed between the propeller bladesand the disc B1, only a small amount of pressure is necessary to varythe pitch. It has been found that oil soaked felt may be used upon thering 69 to provide the necessary friction, and that such felt will standup under the necessary pressure. If necessary, other materials may beused, however, to provide the necessary friction between the ring 69 andthe disc 61 to act to change the pitch of the blades 21.

In accordance with the patent statutes, I have described the principlesof construction and operation of my variable pitch propeller; and whileI have endeavored to set forth the best embodiment thereof, I desire tohave it understood that this is only illustrative of a means of carryingout my invention, and that obvious changes may be made within the scopeof the following claims without departing from the spirit of myinvention.

I claim:

1. A variable pitch propeller comprising a propeller shaft, a bladesupport mounted thereon, blades mounted on said support, gear meansrotatably connecting said blade means to rotate the same axially inunison, a large gear means connected to said gear means, a pinionengaging said large gear means, a gear large relativevto said pinionrotatable with said pinion, a second pinion engaging said last namedlarge gear, a rotatable peller shaft., a blade support mounted thereon,

blades mounted on said support, gear means rotatably connecting saidblades to rotate said blades axially in unison, a large gear meansconnected to said gear means, a rotatable disc encircling said shaft, aseries of reduction gears Vconnected to said rotatable connecting means,

said gears and disc normally rotating in a body with said shaft, astationary friction disc element engageable with said disc, and governormeans driven by said shaft moving said friction disc element againstsaid disc upon an increase in speed of said shaft to' create relativerotation be- EDWARD LINEHAN.

